Ch4
Manual
(2.0E)
General Information
Ch4 Manual
Version 2.0E, 10/2003, D2055.E.02
©
by d&b audiotechnik AG 2003; all rights reserved.
The information contained in this manual has been carefully
checked for accuracy, at the time of going to press, however no
guarantee is given with respect to the correctness.
d&b audiotechnik AG accepts no responsibility for any errors or
inaccuracies that may appear in this manual or the products and
software described in it.
Technical specifications, dimensions, weights and properties do not
represent guaranteed qualities.
As manufacterers we reserve the right to make alterations and
modifications within the framework of legal provisions, as well as
changes aimed at improving quality.
d&b audiotechnik AG
Eugen-Adolff-Strasse 134, D-71522 Backnang, Germany
Telephone +49-7191-9669-0, Fax +49-7191-95 00 00
E-mail: [email protected], Internet: www.dbaudio.com
References in the manual
WARNING!
This refers to a potentially dangerous situation
which may lead to personal injury.
CAUTION!
This refers to a potentially dangerous situation
which may lead to damage to the equipment.
IMPORTANT!
This refers to a situation which may cause the
equipment to malfunction.
Symbols on the equipment
Please refer to the information in the operating
manual.
WARNING!
Dangerous voltage!
Ch4 Manual (2.0E) Page 3 of 8
Ch4 Manual (2.0E) Safety instructions
Safety precautions
Before you use our products, read the manual
carefully and observe all the safety precautions.
They will protect you and help to avoid equipment
failures.
Keep this manual in a safe place so that it is
available for future reference.
If you supply d&b products, please draw the
attention of your customers to these safety
guidelines. Enclose the relevant manuals with the
systems. If you require additional manuals for this
purpose, you can order them from d&b.
Information regarding use of loudspeakers
WARNING!
Never stand in the immediate vicinity of loudspeakers driven at a
high level. Professional loudspeaker systems are capable of causing
a sound pressure level detrimental to human health. Seemingly non-
critical sound levels (from approx. 95 dB SPL) can cause hearing
damage if people are exposed to it over a long period.
In order to prevent accidents when deploying loudspeakers on the
ground or when flown, please take note of the following:
When setting up the loudspeakers or loudspeaker stands, make sure
they are standing on a firm surface. If you place several systems on
top of one another, use straps to secure them against movement.
Only use accessories which have been tested and approved by d&b
for assembly and mobile deployment. Pay attention to the correct
application and maximum load capacity of the accessories as
detailed in our specific “Mounting instructions” or in our "Flying
system and Rigging manuals”.
Ensure that all additional hardware, fixings and fasteners used for
installation or mobile deployment are of an appropriate size and
load safety factor. Pay attention to the manufacturers instructions
and to the relevant safety guidelines.
Regularly check the loudspeaker housings and accessories for visible
signs of wear and tear, and replace them when necessary.
Regularly check all load bearing bolts in the mounting devices.
CAUTION!
Loudspeakers produce a static magnetic field even if they are not
connected or are not in use. Therefore make sure when erecting
and transporting loudspeakers that they are nowhere near
equipment and objects which may be impaired or damaged by an
external magnetic field. Generally speaking, a distance of 0.5 m
(1.5 ft) from magnetic data carriers (floppy disks, audio and video
tapes, bank cards, etc.) is sufficient; a distance of more than 1 m
(3 ft) may be necessary with computer and video monitors.
Ch4 Manual (2.0E) Page 4 of 8
Ch4
The Ch4 loudspeaker is the skeletal version of the Ci4-TOP (C4-
TOP) loudspeaker. It is acoustically compatible with the respective
Ci4-TOP (C4-TOP) differing only in the mechanical construction.
The Ch4 loudspeaker is a mid to high range loudspeaker which
uses a coaxial array of two constant directivity horns. Two
passively coupled drivers are used a 12“ low frequency driver with
a 4“ voice coil and a specially treated diaphragm and a 2“ exit
compression driver with a titanium diaphragm. The nominal
35
°
x 35
°
dispersion is maintained down to 700 Hz.
The Ch4 is constructed from paint finished fibreglass reinforced
plastic (GRP). The Ch4 weighs approximately 31 kg /68 lb.
CAUTION!
Only operate Ch4 cabinets with a d&b D12 or E-PAC amplifier in
C4-TOP configuration or a P1200A mainframe fitted with a C4-
TOP controller module, otherwise there is a risk of damaging the
loudspeaker components.
Connections
Ch4 cabinets are fitted with two NL4 connectors wired in parallel
and are driven using pins 1+/1
–
.
Operation with D12
Selecting C4-TOP mode in the D12 enables up to two Ch4
cabinets to be driven by each channel. In applications with low
continuous levels and low ambient temperatures up to three
loudspeakers per channel may be connected.
Controller settings
For acoustic adjustment the functions HFC and CPL can be selected.
HFC circuit
20
100
1k
10k
20k
2
0
4
6
-2
-4
dB
Frequency response of HFC circuit
In HFC mode (High Frequency Compensation), the response of the
system is tailored for remote listening positions. The characteristics
of HFC mode are detailed in the graph opposite.
Selecting HFC compensates for loss of high frequency energy due
to absorption in air when loudspeakers are used to cover far field
listening postions. The HFC correction equates to the HF loss which
occurs at a distance of 30 m (100 ft) at 20
°
C (68
°
F) in 50 %
relative humidity.
Ch4 Manual (2.0E) Page 5 of 8
CPL circuit
Frequency response of CPL circuit
The CPL (Coupling) circuit compensates for coupling effects
between the cabinets when building closely coupled arrays. CPL
begins gradually at 1 kHz, with maximum attenuation below
250 Hz, providing a balanced frequency response when Ch4
cabinets are used in arrays of two or more. The function of the CPL
circuit in the D12 amplifier is shown in the diagram opposite and
can be set in dB attenuation values between –9 and 0.
Operation with E-PAC (Version 3 with display only)
Selecting C4-TOP mode in the E-PAC enables one Ch4 cabinet to
be driven at an output power of 300 Watts. LO IMP mode allows
the E-PAC to drive two Ch4 cabinets with a 6 dB reduction of input
level to the speakers.
The HFC setting is available. The characteristics of the HFC setting
is explained under the previous section "Operation with D12 -
Controller settings".
Operation with P1200A
C4-TOP
Controls on C4-TOP
controller module
Up to two Ch4 cabinets can be driven by each P1200A power
amplifier channel fitted with a C4-TOP controller module. Fitting
one C4-TOP and one subwoofer controller module allows a single
mainframe to drive two Ch4 and two active subwoofer cabinets.
The HFC setting is available. The characteristics of the HFC setting
is explained under the previous section "Operation with D12 -
Controller settings".
Ch4 Manual (2.0E) Page 6 of 8
Dispersion characteristics
The diagrams below show dispersion angle vs frequency plotted
using lines of equal sound pressure (isobars) at -6 dB and -12 dB.
The nominal 35
°
dispersion is maintained from 16 kHz down to
700 Hz. Horizontal and vertical characteristics are identical.
Ch4 isobar diagram
Technical specifications
Ch4 system data
Frequency response (–5 dB)....................................................................150 Hz - 18 kHz
Max. sound pressure (1 m, free field) with D12 ................................................ 140 dB
Max. sound pressure (1 m, free field) with E-PAC ............................................. 136 dB
Max. sound pressure (1 m, free field) with P1200A ......................................... 138 dB
(SPLmax peak, pink noise test signal with crest factor of 4)
Input level (SPLmax) ................................................................................................. +14 dBu
Input level (100 dB SPL / 1 m)...............................................................................–21 dBu
Polarity to controller INPUT (XLR pin 2: + / 3: –) ..................................LF: + / HF: +
Ch4 loudspeaker
Nominal impedance................................................................................................... 8 ohms
Power handling capacity (RMS / peak 10 ms)........................................ 200 / 800 W
Nominal dispersion angle (hor. x vert.).............................................................35
°
x 35
°
Connections .................................................................................................................. 2x NL4
Pin assignments .......................................................................................................... 1+ / 1–
Weight .................................................................................................................31 kg (68 lb)
-5
0
5
10
-10
-15
-20
-25
-30
20
100 1k 10k
20k
Ch4 frequency response
Ch4 Manual (2.0E) Page 7 of 8
Ch4 wiring diagram
235
[
9.25"
]
5
4
0
[21.3"]
0
460
[
18.1"
]
560
[
22.05"
]
6
1
0
[
24.02"
]
5
4
0
[
21.3"
]
42
0
[
16.5"
]
300
[5.5"]
8.5
[
0.33"
]
10.5
[
0.41"
]
Ch4 cabinet dimensions in mm [inch]
Ch4 Manual (2.0E) Page 8 of 8
d&b audiotechnik AG, Eugen-Adolff-Str. 134, D-71522 Backnang, Germany, Phone +49-7191-9669-0, Fax +49-7191-95 00 00
EU declaration of conformity (CE symbol)
EU conformity of loudspeakers
This declaration applies to loudspeakers manufactured by d&b
audiotechnik AG and includes the types listed in the table below:
−
Ch4 Z2265
All production versions of these types are included, provided they
correspond to the original technical version and have not been
subject to any later design or electromechanical modifications.
We herewith declare that said products are in
conformity with the provisions of the following EC
directives including all applicable amendments:
−
89/336 Electromagnetic Compatibility
The following standards have been applied:
−
DIN EN 55013:08-1991
−
DIN EN 55020:05-1995
−
DIN EN 50082-1:03-1993
/
